Characterization and Mineralization of Strontium Doped Nano Hydroxyapatite Coating on Titanium Rods

Abstract

Pure nano hydroxyapatite (nHA) and strontium doped nano hydroxyapatite (Sr-nHA, Sr/(Ca+Sr) =10%) were prepared by a one-step method which mainly used the principle of homogeneous phase co-precipitation. Fourier transform infrared spectroscopy (FT-IR) revealed that the intensity of absorption was decreased with Sr doping. X-ray diffraction (XRD) showed that special peak position of Sr-nHA shifted to a smaller 2θ angle compared with the pure nHA. Both the pure nHA (39.46±11.19nm in length and 15.90±3.65 nm in width) and Sr-nHA (32.95±10.21 nm in length and 13.18±3.18 nm in width) samples showed a tiny nano-rod feature. Moreover, Tc4 (Ti-6Al-4V) rods (1 mm in diameter and 20 mm in length) coated with pure nHA or Sr-nHA were prepared by high-energy plasma spraying. Elements of calcium (Ca), phosphorus (P), oxygen (O) and Sr were detected on the Sr-nHA coating surface by Energy Dispersive Spectrometry (EDS). XRD result also indicates the chemical composition almost did not change significantly after spraying. By immersion in the simulated body fluid (SBF), in vitro mineralization ability was estimated and the superficial coats were evaluated by scanning electron microscopy (SEM) and XRD. The results showed that Sr-nHA spraying surface has a better mineralization ability than the pure nHA coating. Therefore, the synthesized Sr-nHA would have potential for biological prostheses and other implantable materials.

DOI: http://dx.doi.org/10.5755/j01.ms.23.3.17254